In this article, we describe the construct validation of a General Social Attitudes Scale (SAS_G), designed to measure the basic dimensions of social attitudes in both self-reports and peer-ratings. A large sample of Croatian university students (N = 452) used the SAS_G to describe their own social attitudes, which were also described by 452 of their acquaintances using the same instrument. All SAS_G subscales showed reasonably high internal consistency reliability estimates as well as appropriate convergent and discriminant validity based on self/peer correlations. Separate Confirmatory Factor Analyses (CFA) of both self-reports and peer ratings yielded five replicable factors and acceptable indices of fit. However, the validation analyses against lexically based Saucier’s (2008) ISMS instrument showed little convergence, indicating that these two approaches to general social attitudes scale construction can lead to the identification of different basic constructs.